Influence of Rubber Powder Content on High-Temperature Performance of TOR Rubber Asphalt

2013 ◽  
Vol 405-408 ◽  
pp. 1753-1756
Author(s):  
Yong Mei Guo ◽  
Wei Chen

Six kinds of TOR rubber asphalts with 5%-30% rubber powder contents of were selected to carry out conventional high-temperature tests and dynamic shear rheological tests to obtain some parameters reflecting the high-temperature performance of asphalt binders, such as softening point, dynamic viscosity at 60°C, rutting factor (G*/sinδ) at 60°C and critical temperature of rutting factor (TG*/sinδ). The results show that the changing tendency of two rheological parameters of TOR rubber asphalts, G*/sinδ at 60°C and TG*/sinδ, is ascend in first and descend at last with the increase of rubber powder content proportion. The high-temperature performance of TOR rubber asphalt with the rubber powder content about 20% is the best. Softening point and dynamic viscosity at 60°C, as two conventional high-temperature parameters of asphalt binders, can describe the high-temperature performance of TOR rubber asphalt with the rubber powder content below 20%, but cannot evaluate accurately the high-temperature performance of TOR rubber asphalt with the rubber powder content above 20%, because TOR rubber asphalt has formed a network structure at this moment.

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6229
Author(s):  
Krzysztof Maciejewski ◽  
Piotr Ramiączek ◽  
Eva Remisova

The presented study explores the effects of decreased temperatures utilized in rolling thin-film oven (RTFOT) laboratory short-term ageing of asphalt binders based on 35/50- and 50/70-penetration paving-grade bitumen. Additionally, the effects of three additives used with these binders at different concentrations are evaluated: liquid anti-stripping agent, liquid warm-mix additive, and solid warm-mix additive. The resulting asphalt binders were subjected to basic (penetration at 25 °C, softening point, dynamic viscosity) and functional high-temperature characterization (G*/sin(δ), high critical temperature, non-recoverable creep compliance). It was found that the decreased short-term ageing temperatures may detrimentally impact the high-temperature grade of bituminous binders, but this effect can be mitigated by the use of appropriate additives. What is more, it was found that bituminous binders may respond differently to the aforementioned factors. Based on the results, it is advised that asphalt binders intended for use in warm-mix asphalts should be thoroughly tested to appropriately simulate the mixture production process and its effects.


2009 ◽  
Vol 614 ◽  
pp. 197-200 ◽  
Author(s):  
Shao Peng Wu ◽  
Gang Liu ◽  
Jin Gang Wang ◽  
Yuan Zhang

In this study, the influence of some inorganic nanoparticles on the properties of bitumen binder was investigated. Three types of particles at nanometer level, calcium carbonate powder, graphite and carbon black, were introduced to modify bitumen respectively. The modified binders were prepared using a laboratory high-shear mixer. A dynamic shear rheometer (DSR) was adopted to characterize the properties of modified binders, including their rheological parameters and dynamic viscosity, over a certain range sweeps of temperatures, frequencies and shear rates. It was found that the addition of the nanoparticles increased the binder’s elasticity at low temperature which might negatively influence its resistance to crack. However the decrease of phase angle at high temperature might improve its deformation resistance. The shear rate dependence of dynamic viscosity for the binders depended on the type of nanoparticle. The research results indicated that the addition of nanoparticles to bitumen binder can change its physical properties to some extent and its potential should be researched further.


Alloy Digest ◽  
1985 ◽  
Vol 34 (7) ◽  

Abstract ALLEGHENY STAINLESS Type 405, unlike most other 12% chromium steels, is not subject to appreciable hardening through air cooling from high temperatures. This is an advantageous characteristic in those applications where a soft, ductile material is required after rapid cooling from above the critical temperature. The nonhardening tendency of Type 405 also retards the formation of hardening cracks where welding is employed. Its uses include annealing boxes and baffles where hardening during cooling would be undesirable. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as heat treating and machining. Filing Code: SS-461. Producer or source: Allegheny Ludlum Corporation.


Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2585
Author(s):  
Zhelun Li ◽  
Xin Yu ◽  
Yangshi Liang ◽  
Shaopeng Wu

Effective thermal conduction modification in asphalt binders is beneficial to reducing pavement surface temperature and relieving the urban heat island (UHI) effect in the utilization of solar harvesting and snow melting pavements. This study investigated the performance of two nanometer-sized modifiers, graphene (Gr) and carbon nanotubes (CNTs), on enhancing the thermal, physical and rheological properties of asphalt binders. Measurements depending on a transient plant source method proved that both Gr and CNTs linearly increased the thermal conductivity and thermal diffusivity of asphalt binders, and while 5% Gr by volume of matrix asphalt contributed to 300% increments, 5% CNTs increased the two parameters of asphalt binders by nearly 72% at 20 °C. Meanwhile, a series of empirical and rheological properties experiments were conducted. The results demonstrated the temperature susceptibility reduction and high-temperature properties promotion of asphalt binders by adding Gr or CNTs. The variation trends in the anti-cracking properties of asphalt binders modified by Gr and CNTs with the modifier content differed at low temperatures, which may be due to the unique nature of Gr. In conclusion, Gr, whose optimal content is 3% by volume of matrix asphalt, provides superior application potential for solar harvesting and snow melting pavements in comparison to CNTs due to its comprehensive contributions to thermal properties, construction feasibility, high-temperature performance and low-temperature performance of asphalt binders.


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Jiupeng Zhang ◽  
Guoqiang Liu ◽  
Li Xu ◽  
Jianzhong Pei

Sasobit additives with different dosages were added into 70# and 90# virgin asphalt binders to prepare WMA binders. The rheological properties, includingG∗andδ, were measured by using DSR at the temperature ranging from 46°C to 70°C, and the effects of temperature, additive dosage and aging onG∗/sin⁡δ, critical temperature, and H-T PG were investigated. The results indicate that WMA additive improvesG∗but reducesδ, and the improvement on 70# virgin binder is more significant.G∗/sin⁡δexponentially decreases with the increasing temperature but linearly increases with the increasing additive dosage. Aging effect weakens the interaction between binder and additive but significantly increases the binder’s viscosity; that is whyG∗/sin⁡δis higher after short-term aging. In addition, the critical temperature increases with the increasing additive dosage, and the additive dosage should be more than 3% and 5% to improve H-T PG by one grade for 70# and 90# virgin binder, respectively.


2015 ◽  
Vol 16 (sup1) ◽  
pp. 211-227 ◽  
Author(s):  
Jean-Claude Carret ◽  
Augusto Cannone Falchetto ◽  
Mihai O. Marasteanu ◽  
Hervé Di Benedetto ◽  
Michael P. Wistuba ◽  
...  

2011 ◽  
Vol 84-85 ◽  
pp. 662-666 ◽  
Author(s):  
Zeng Ping Zhang ◽  
Yong Wen ◽  
Jian Zhong Pei ◽  
Shuan Fa Chen

Montmorillonite (MMT) modified asphalts are prepared by melt blending with the help of high-speed shear mixer. The dispersion of MMT layers in the asphalt matrix are characterized by X-ray diffraction (XRD). The effect of different contents of MMT on physical properties of the base asphalt is studied. These properties include penetration, softening point and ductility. The results indicate that MMT/asphalt may form a nanocomposite structure with MMT layers intercalated by the asphalt molecules. MMT can improve the high temperature performance and temperature sensitivity of the base asphalt. And it can slightly reduce the low temperature performances of matrix asphalt. It is found that low temperature performances, high temperature performance and temperature sensitivity of the modified system achieved balance when the content of MMT is 4 wt%.


2021 ◽  
Vol 7 ◽  
Author(s):  
Hengxiao Xue ◽  
Yuanbo Cao ◽  
Qi Liu ◽  
Hongfei Zhang ◽  
Mingliang Zhang

Ground tires are one of the main sources of urban solid waste. Rubber powder-modified asphalt provides an effective method to solve the problem, and it presents good high- and low-temperature performance in sustainable pavement construction. However, the storage properties of rubber powder-modified asphalts prepared from the traditional low-temperature shear mixing method are unstable, which restricts their application. In this study, four test methods (the softening-point test; the dynamic shear rheological test; the Laboratory Asphalt Stability Test; and fluorescence image analysis) and six evaluation indexes (the softening-point difference Sdiff, the segregation percentage Sp, the segregation index Ise, the segregation rate Rs, the degradation rate Rd, and the stability index Ist) were employed to analyze the storage abilities of asphalts modified by various activated rubber powder contents. The results show that the storage properties have a positive correlation with rubber powder content in the modified asphalt, and a rubber powder content of 60% is proven to be the optimum mixing amount. The rubber powders can distribute uniformly in the asphalt matrix when mixed below the optimum mixing amount; otherwise a rubber powder agglomeration is formed. The quantitative morphology analysis results are in good agreement with the laboratory test conclusions. The activated rubber powder shows better compatibility compared with ordinary rubber powders and presents a promising method to treat waste ground tires.


2021 ◽  
Vol 13 (18) ◽  
pp. 10271
Author(s):  
Yuchen Guo ◽  
Xuancang Wang ◽  
Guanyu Ji ◽  
Yi Zhang ◽  
Hao Su ◽  
...  

The deteriorating ecological environment and the concept of sustainable development have highlighted the importance of waste reuse. This article investigates the performance changes resulting from the incorporation of shellac into asphalt binders. Seashell powder-modified asphalt was prepared with 5%, 10%, and 15% admixture using the high-speed shear method. The microstructure of the seashell powder was observed by scanning electron microscope test (SEM); the physical-phase analysis of the seashell powder was carried out using an X-ray diffraction (XRD) test; the surface characteristics and pore structure of shellac were analyzed by the specific surface area Brunauer-Emmett-Teller (BET) test; and Fourier infrared spectroscopy (FTIR) qualitatively analyzed the composition and changes of functional groups of seashell powder-modified asphalt. The conventional performance index of seashell powder asphalt was analyzed by penetration, softening point, and ductility (5 °C) tests; the effect of seashell powder on asphalt binder was studied using a dynamic shear rheometer (DSR) and bending beam rheometer (BBR) at high and low temperatures, respectively. The results indicate the following: seashell powder is a coarse, porous, and angular CaCO3 bio-material; seashell powder and the asphalt binder represent a stable physical mixture of modified properties; seashell powder improves the consistency, hardness, and high-temperature performance of the asphalt binder but weakens the low-temperature performance of it; seashell powder enhances the elasticity, recovery performance, and permanent deformation resistance of asphalt binders and improves high-temperature rheological properties; finally, seashell powder has a minimal effect on the crack resistance of asphalt binders at very low temperatures. In summary, the use of waste seashells for recycling as bio-modifiers for asphalt binders is a practical approach.


2021 ◽  
Vol 10 (1) ◽  
pp. 1801-1811
Author(s):  
Xiaolong Sun ◽  
Yikang Zhang ◽  
Qinyuan Peng ◽  
Junshen Yuan ◽  
Zhi Cang ◽  
...  

Abstract To clarify the influence of geometric parameters of parallel plate on rheological properties of polyurea elastomer (PUA)-modified asphalt, nano-PUA powder was prepared, and nano-PUA powder modifier was modified by using high-speed shearing apparatus. The apparent viscosity of modified asphalt was evaluated by Brookfield viscosity. The rheological parameters of PUA-modified asphalt were determined by comparing the rheological test results of temperature scanning, frequency scanning, and multiple stress creep recover test using 8 and 25 mm parallel plates. Results indicated that the higher the content of nano-PUA modifier was, the better the high-temperature performance of asphalt would be. When using the 8 mm parallel plate, the high-temperature performance of modified asphalt was worse than that of matrix asphalt, and the PUA modifier would lead to a negative effect on the rheological property of asphalt. Regarding the 25 mm parallel plate, the high-temperature performance of modified asphalt was better than that of matrix asphalt, which was contrary to the results of 8 mm parallel plate. The rheological test results using 25 mm parallel plate were consistent with the results of Brookfield viscosity, indicating that 25 mm parallel plate was more suitable for evaluating the rheological performance of PUA-modified asphalt.


Sign in / Sign up

Export Citation Format

Share Document